rleqs, cleqs

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These functions implements an interface for the LAPACK functions DGESV, ZGESV, DGELS and ZGELS.

Usage
rleqs(A, B {, alg}):
A
left side MxN matrix x
B
right side vector or MxL matrix (for multiple solutions)
alg
select a LAPACK algorithm to be used
{class="keinrahmen"

|alg=0 || use DGESV if M=N and DGELS otherwise |- |alg=1 || use always DGESV, M must be equal to N |- |alg=2 || use always DGELS |}

Description
m
the regression (polynom) order; m>0 (default=1)
Result 1
Approximate the function y using polynominal regression. The result is the vector r with the m+1 coefficients of the regression polynom.
yREG[i] = r[0] + r[1]*x[i] {+ r[2]*x[i]^2 + .. + r[m]*x[i]^m}

Note: The function cleqs(A, B {, alg}) has the same arguments and result as rleqs, but the vectors/matrices A, B and X are complex.

Usage 2
rpolyreg(xmatrix, yvector {, m}):
x
x data matrix, the regression order is the number of independent variables m=ncol(x)
y
y data vector: y[i] = f(x[i,*])
Result 2
Approximate the function y using multivariant linear regression. The result is the vector r with the m+1 regression coefficients.
yREG[i] = r[0] + r[1]*x[i,0] + .. + r[m]*x[i,m-1]

See also
rpoly, interp, rleqs, cleqs

<function list>

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